A nationwide study by Harvard researchers reveals that U.S. counties closer to operating nuclear power plants have higher cancer mortality rates, even after adjusting for socioeconomic and health factors. The analysis covers data from 2000 to 2018 across all U.S. counties and nuclear facilities. While the findings do not establish causation, they highlight the need for further research on potential health impacts.
Researchers from the Harvard T.H. Chan School of Public Health conducted the first comprehensive 21st-century analysis of cancer mortality and proximity to nuclear power plants in the United States. The study, published in Nature Communications on February 23, 2026, examined data from every operating nuclear power plant and all U.S. counties between 2000 and 2018.
The team employed a 'continuous proximity' method to assess distances from counties to multiple nearby facilities, using location and operating history data from the U.S. Energy Information Administration, including some Canadian plants. Cancer mortality statistics came from the Centers for Disease Control and Prevention. Adjustments were made for variables such as educational attainment, median household income, racial composition, average temperature, relative humidity, smoking prevalence, body mass index, and distance to the nearest hospital.
Results showed that counties nearer to nuclear power plants experienced elevated cancer death rates, particularly among older adults. The researchers estimated that about 115,000 cancer deaths nationwide over the period—roughly 6,400 annually—were associated with this proximity.
"Our study suggests that living near a NPP may carry a measurable cancer risk -- one that lessens with distance," said senior author Petros Koutrakis, Akira Yamaguchi Professor of Environmental Health and Human Habitation. He emphasized the importance of additional studies, especially as nuclear power gains promotion as a clean energy option for addressing climate change.
The findings align with a prior study by the same team in Massachusetts, which observed higher cancer incidence near nuclear facilities there. However, limitations include the absence of direct radiation measurements and an assumption of uniform plant impacts, meaning the association does not confirm that nuclear plants directly cause increased cancer deaths.
Previous U.S. research had focused on individual facilities, yielding inconsistent results globally. This broader approach underscores patterns warranting deeper investigation without implying definitive links.
